Information detailing Iran's progress was in an update from the International Atomic Energy Agency, which has been conducting inspections of Iran's main nuclear facility at Natanz. The report concluded that, as of earlier in November, Iran produced about 1,390 pounds of low-enriched uranium, The New York Times reported Thursday.

Several experts told the Times that amount was enough for a bomb, adding that more work was needed to actually create the weapon. Not only would Tehran have to renege on its agreements and boot inspectors, it also would have to further purify the fuel and put it in a warhead design.

"They clearly have enough material for a bomb," Richard L. Garwin, a nuclear physicist who helped invent the hydrogen bomb and has advised U.S. officials, told the Times. "They know how to do the enrichment. Whether they know how to design a bomb, well, that's another matter."

Iran has maintained its nuclear program is for peaceful purposes. However, many Western nations say they suspect the true purpose is to gain nuclear weapons-making capability.

The IAEA said Iran was avoiding questions about its suspected work on nuclear warheads. The report also said In the Natanz plant was feeding uranium into about 3,800 centrifuges, the same number as in the agency's September quarterly report.